A glass composition includes greater than or equal to 60 mol % and less than or equal to 85 mol % SiO.sub.2; greater than or equal to 0.5 mol % and less than or equal to 20 mol % Al.sub.2O.sub.3; greater than or equal to 0 mol % and less than or equal to 15 mol % Li.sub.2O; greater than or equal to 0.5 mol % and less than or equal to 25 mol % Na.sub.2O; greater than or equal to 0.1 mol % and less than or equal to 20 mol % K.sub.2O; greater than or equal to 0 mol % and less than or equal to 10 mol % CaO; greater than or equal to 0 mol % and less than or equal to 10 mol % MgO; and greater than or equal to 0.005 mol % and less than or equal to 0.5 mol % Au.

A method for manufacturing a motor vehicle roof incorporating a glazing, in which at least one opacifying layer of ink(s), in particular at least one layer of colored ink(s), is applied by digital printing, in particular by inkjet, over at least 40% of the surface of one of the faces of at least one glass sheet, such that the composition of said ink(s) includes at least one glass frit, and where applicable one or more inorganic pigment(s), with a D90 value for the particle size distribution of less than 2 m, and such that the ink(s) have a viscosity of between 1 and 50 mPa.Math.s, the ink(s) further including a non-stick agent and/or a non-stick component and/or at least one non-stick agent and/or at least one non-stick layer being further applied to at least one layer of ink(s) and/or to at least one glass sheet.

A method for manufacturing a motor vehicle roof incorporating a glazing, in which at least one opacifying layer of ink(s), in particular at least one layer of colored ink(s), is applied by digital printing, in particular by inkjet, over at least 40% of the surface of one of the faces of at least one glass sheet, such that the composition of said ink(s) includes at least one glass frit, and where applicable one or more inorganic pigment(s), with a D90 value for the particle size distribution of less than 2 m, and such that the ink(s) have a viscosity of between 1 and 50 mPa.Math.s, the ink(s) further including a non-stick agent and/or a non-stick component and/or at least one non-stick agent and/or at least one non-stick layer being further applied to at least one layer of ink(s) and/or to at least one glass sheet.

A method for manufacturing a motor vehicle roof incorporating a glazing, in which at least one opacifying layer of ink(s), in particular at least one layer of colored ink(s), is applied by digital printing, in particular by inkjet, over at least 40% of the surface of one of the faces of at least one glass sheet, such that the composition of said ink(s) includes at least one glass frit, and where applicable one or more inorganic pigment(s), with a D90 value for the particle size distribution of less than 2 ?m, and such that the ink(s) have a viscosity of between 1 and 50 mPa.Math.s, the ink(s) further including a non-stick agent and/or a non-stick component and/or at least one non-stick agent and/or at least one non-stick layer being further applied to at least one layer of ink(s) and/or to at least one glass sheet.

A method for manufacturing a motor vehicle roof incorporating a glazing, in which at least one opacifying layer of ink(s), in particular at least one layer of colored ink(s), is applied by digital printing, in particular by inkjet, over at least 40% of the surface of one of the faces of at least one glass sheet, such that the composition of said ink(s) includes at least one glass frit, and where applicable one or more inorganic pigment(s), with a D90 value for the particle size distribution of less than 2 ?m, and such that the ink(s) have a viscosity of between 1 and 50 mPa.Math.s, the ink(s) further including a non-stick agent and/or a non-stick component and/or at least one non-stick agent and/or at least one non-stick layer being further applied to at least one layer of ink(s) and/or to at least one glass sheet.

A glass-ceramic article comprises a petalite crystalline phase and a lithium silicate crystalline phase. The weight percentage of each of the petalite crystalline phase and the lithium silicate crystalline phase in the glass-ceramic article are greater than each of the weight percentages of other crystalline phases present in the glass-ceramic article. The glass-ceramic article has a transmittance color coordinate in the CIELAB color space of: L*=from 20 to 90; a*=from ?20 to 40; and b*=from ?60 to 60 for a CIE illuminant F02 under SCI UVC conditions. In some embodiments, the colorant is selected from the group consisting of TiO.sub.2, Fe.sub.2O.sub.3, NiO, CO.sub.3O.sub.4, MnO.sub.2, Cr.sub.2O.sub.3, CuO, Au, Ag, and V.sub.2O.sub.5.

A glass-ceramic article comprises a petalite crystalline phase and a lithium silicate crystalline phase. The weight percentage of each of the petalite crystalline phase and the lithium silicate crystalline phase in the glass-ceramic article are greater than each of the weight percentages of other crystalline phases present in the glass-ceramic article. The glass-ceramic article has a transmittance color coordinate in the CIELAB color space of: L*=from 20 to 90; a*=from ?20 to 40; and b*=from ?60 to 60 for a CIE illuminant F02 under SCI UVC conditions. In some embodiments, the colorant is selected from the group consisting of TiO.sub.2, Fe.sub.2O.sub.3, NiO, CO.sub.3O.sub.4, MnO.sub.2, Cr.sub.2O.sub.3, CuO, Au, Ag, and V.sub.2O.sub.5.

Provided are a fluorescent glass ceramic with high transparency and a preparation method and use thereof. The fluorescent glass ceramic includes the following raw materials by mass percentage: 63 wt % to 70 wt % of SiO.sub.2, 13 wt % to 16 wt % of Li.sub.2O, 1 wt % to 6 wt % of Al.sub.2O.sub.3, 1 wt % to 10 wt % of K.sub.2O, 2 wt % to 6 wt % of P.sub.2O.sub.5, 0.5 wt % to 3.5 wt % of CeO.sub.2, 0 wt % to 4 wt % of an additive, 1 wt % to 4 wt % of a lanthanide oxide with an atomic number of 59 to 71, and 0 wt % to 8 wt % of a colorant. The fluorescent glass ceramic has a lithium metasilicate crystal as a principal crystalline phase, and the lithium metasilicate crystal has a layered or plate-like structure and a grain size of 0.1 ?m to 1.5 ?m.

Provided are a fluorescent glass ceramic with high transparency and a preparation method and use thereof. The fluorescent glass ceramic includes the following raw materials by mass percentage: 63 wt % to 70 wt % of SiO.sub.2, 13 wt % to 16 wt % of Li.sub.2O, 1 wt % to 6 wt % of Al.sub.2O.sub.3, 1 wt % to 10 wt % of K.sub.2O, 2 wt % to 6 wt % of P.sub.2O.sub.5, 0.5 wt % to 3.5 wt % of CeO.sub.2, 0 wt % to 4 wt % of an additive, 1 wt % to 4 wt % of a lanthanide oxide with an atomic number of 59 to 71, and 0 wt % to 8 wt % of a colorant. The fluorescent glass ceramic has a lithium metasilicate crystal as a principal crystalline phase, and the lithium metasilicate crystal has a layered or plate-like structure and a grain size of 0.1 ?m to 1.5 ?m.

A rotary mill for grinding recycled glass materials into particles has a housing defining an impact chamber with a rotor in the chamber at the bottom of an inclined guide wall underneath the feed opening. The rotor has a plurality of axially extending, angularly spaced massive impact hammers so that the impact hammers impact and deflect the solid materials onto a plurality of shatter bars located at the peripheral wall. Each of the impact hammers has a leading blade element of a hardened steel which has a front face inclined relative to a bottom portion of the guide surface so that an outer edge of the front face is angularly advanced relative to an inner edge thereof.